1 Enoch

And after that the Head of Days repented and said: ' In vain have I destroyed all who dwell on the earth.'

And He sware by His great name: ' Henceforth I will not do so to all who dwell on the earth, and I will set a sign in the heaven : and this shall be a pledge of good faith between Me and them for ever, so long as heaven is above the earth. And this is in accordance with My command.